The present invention relates generally to a coupling device for detachably connecting an eyepiece of an endoscope optical system with a camera lens.
Coupling devices are used to take an eyepiece of an endoscopic instrument otherwise used for viewing with the eye and connect it to a camera. Such a coupling device is known from DE 69 26 837 U. This device provides a ring element that can be screwed into the distal end of a lens casing. An inner ring engages into the ring element, forming a receptacle for the proximal end section of an eyepiece shaped like a truncated cone. Several radial boreholes are distributed over the periphery of the inner ring, which are each used for accommodating a locking sphere. The inner ring is enveloped by a rotatable, annular handle. The inner periphery of this handle exhibits oblong recesses that correspond to the boreholes of the inner ring, and become continuously deeper in the peripheral direction of the handle. The handle is preloaded by a spring against its rotational direction relative to the ring element. In an eyepiece not introduced in the inner ring, the locking spheres are always in their position that otherwise fixes the conical section of the eyepiece in place. In order to introduce the eyepiece into the inner ring, the handle must be turned against its preloaded spring in such a way that the locking spheres can engage into the recesses formed on the handle at their deepest location. Letting go of the handle causes it to be moved by the released spring, thereby pressing the locking spheres inward into the boreholes of the inner ring as the depth of the recesses in the handle decreases, where they then project out of the inner periphery of the inner ring, enveloping the conical section of the eyepiece, fixing it in place in this way. To release the eyepiece in the coupling device, the handle must again be turned against its preloaded spring, so that the locking spheres can again move to the outside, meaning away from the eyepiece, in the recesses formed on the handle.